The X-carve, using the Arduino/gShield or X-Controller, uses a serial port for operation of the machine. Anything that can read/write to a serial port has the capability of running the X-carve to use all of its features. There is no requirement to use Easel for anything.

Easel is a program that is the only program that I know of that will create and carve a project from beginning to end. One stop shopping so to speak. I understand why this is a popular selection.

Those that choose to use a different work flow (be it Vectric products, Fusion 360, whatever) to do their project must then decide how to send the G-code to the X-carve. There are many alternatives to use for this purpose rather than using Easel. A glaring problem with Easel as a G-code sender is that it will not send a file that has arc commands (G2/G3) in it.

Here is my question:

Why do people that use alternative CAD/CAM software go back to use Easel for sending the G-code?

I at one time did the same and for me I think it had to do with it being the program i had taught myself to use. Kind of like at my place of work when we perform a task then they find a better way and even though the new way is easier, faster and more efficient people will still revert to the old method it’s just a human nature thing I guess.

Not sure why. Everything that is automated in Easel such as probing etc. can be done with macros in UGS.
But honestly, I have never used Easel. I couldnt get around the paid subscription for program use.